rewrite coverage tests (#9669)

In addition to the speed improvements in CI, the speed improvements locally with both this #9666 which this builds on is even more significant. After it's been run once so it's had a chance to set up the different virtual environments, `tox` locally now takes 39 seconds on my laptop when it used to take 137 seconds.

.coveragerc

@@ -1,5 +1,24 @@
 [run]
 omit = */setup.py
+source =
+    acme
+    certbot
+    certbot-apache
+    certbot-dns-cloudflare
+    certbot-dns-digitalocean
+    certbot-dns-dnsimple
+    certbot-dns-dnsmadeeasy
+    certbot-dns-gehirn
+    certbot-dns-google
+    certbot-dns-linode
+    certbot-dns-luadns
+    certbot-dns-nsone
+    certbot-dns-ovh
+    certbot-dns-rfc2136
+    certbot-dns-route53
+    certbot-dns-sakuracloud
+    certbot-nginx
 
 [report]
 omit = */setup.py
+show_missing = True

tox.ini

@@ -73,8 +73,37 @@ basepython = python3.7
 setenv = CERTBOT_OLDEST=1
 commands = {[testenv:py]commands}
 
-[testenv:cover{,-win,-posix}]
-commands = python tox.cover.py
+[testenv:cover{,-posix}]
+coverage_report = python -m coverage report
+# These coverage report commands are used on both posix and windows
+common_coverage_report_commands =
+    {[testenv:cover]coverage_report} --fail-under 99 --include certbot-dns-cloudflare/*
+    {[testenv:cover]coverage_report} --fail-under 99 --include certbot-dns-digitalocean/*
+    {[testenv:cover]coverage_report} --fail-under 99 --include certbot-dns-dnsimple/*
+    {[testenv:cover]coverage_report} --fail-under 99 --include certbot-dns-dnsmadeeasy/*
+    {[testenv:cover]coverage_report} --fail-under 99 --include certbot-dns-gehirn/*
+    {[testenv:cover]coverage_report} --fail-under 99 --include certbot-dns-google/*
+    {[testenv:cover]coverage_report} --fail-under 100 --include certbot-dns-linode/*
+    {[testenv:cover]coverage_report} --fail-under 99 --include certbot-dns-luadns/*
+    {[testenv:cover]coverage_report} --fail-under 99 --include certbot-dns-nsone/*
+    {[testenv:cover]coverage_report} --fail-under 98 --include certbot-dns-ovh/*
+    {[testenv:cover]coverage_report} --fail-under 99 --include certbot-dns-rfc2136/*
+    {[testenv:cover]coverage_report} --fail-under 94 --include certbot-dns-route53/*
+    {[testenv:cover]coverage_report} --fail-under 99 --include certbot-dns-sakuracloud/*
+    {[testenv:cover]coverage_report} --fail-under 98 --include certbot-nginx/*
+commands =
+    {[testenv:py]commands} --cov --cov-report=
+    {[testenv:cover]coverage_report} --fail-under 100 --include acme/*
+    {[testenv:cover]coverage_report} --fail-under 95 --include certbot/*
+    {[testenv:cover]coverage_report} --fail-under 100 --include certbot-apache/*
+    {[testenv:cover]common_coverage_report_commands}
+
+[testenv:cover-win]
+commands =
+    {[testenv:py-win]commands} --cov --cov-report=
+    {[testenv:cover]coverage_report} --fail-under 99 --include acme/*
+    {[testenv:cover]coverage_report} --fail-under 96 --include certbot/*
+    {[testenv:cover]common_coverage_report_commands}
 
 [testenv:lint{,-win,-posix}]
 commands = python -m pylint --reports=n --rcfile=.pylintrc {[base]source_paths}